Tone-sustaining mechanism



5 1927'. April QCHADWICK TONE SUSTAINING MEoHANIsM Filed Jan. 29, 192e 2 Sheets-Sheet 1 n n AAA. lll

INYENTOR ATTORNEY April 5, 1927. 1,623232 l C. CHADWICK TONE SUSTAINING MECHANISM Filed Jan. 29, 1926 2 Sheets-Sheet 2 lN\ ENTOR ATTOQNEY Patented Apr. 5, 1927.

UNITED STATES CHARLES CHADXVICK, OF BROOKLYN, NEW YORK.

TONE-SUSTAINING MECHANISM.

Application filed January 29, 1926*.

This invention relates to a tone sustaining mcchai'iism for musical instruments and has for its primary object, the provision of a means for causing any sonorous body to vibrate as long as desired.

rThe main object of the invention however, resides in a mechanism for use in connection with a piano. Ordinarily, when the keys of a piano are struck no matter how hard, the tones fade away gradually and the pianist' has no means for controlling them after once struck. Many attempts have been made since tlic piano has been evolved to overcome this, but with little success. One of the best methods so far, has been by the use of electro-magnets, but because the instruments of this type were too complicated and too en pensive, their manufacture was discontinued. My invention relates to an entirely novel method for producing, sustaining and controlling the tones of a piano, or any other musical instrument with the exception of so called wincl-instruments.

With these and other objects in view, the invention resides in certain novel construction and combination and arrangement of parts, the essential features of which are hereinafter fully described, are particularly pointed out in the appended claims, and are illustrated in the accompanying drawing, 1n

which :M

Figure 1 is a fragmentary perspective view of a portion of a piano with my invention applied thereto.

Figure 2 is a vertical transverse sectional view on the line 2 2 ofv Figure 1.

Figures 3 to 7 inclusive illustrate various modified forms of my invention.

Referring more particularly to the drawings and especially to Figures 1 to 5 inclusive, the reference numeral 10 designates the action of a piano and 11 the key board therefor. Although I have illustrated my invention in connection with the pia-no in the preferred form, it will be seen that by reference to Figures 6 and 7 that the same nu be applicable for use upon other types of musical instruments.

The action 10 includes the usual sounding board 12 adjacent to which the strings 13 are strung and are spaced from the board by a bridge 111. Journalled in bearings and extending the length of the action forward of the same, is a rotatable member 15, the same being constructed of ay metal body or core 16 having an outer covering of resinous Serial No. 84,710.

substance 17. The substance 17 may be formed of a layer of thick felt impregnated with rosin or the rosin mixed with hair, wool or paper pulp and evenly applied to the core to provide a friction producing surface on the rotatable member 15.

The key board 11 includes the usual piano keys 18, one for each respective string 13. Slidable rods 19 are operable in an upward vertical direction when the manipulating ends of the keys are depressed, and the said rods drop to normal posit-ion when pressure is released from the keys. Resting' on the upper end of each rod 19 is a pivoted arm 20 which carries a vreed or flat spring 21, to the free end of which is connected one end of a flexible cord 22. The cord passes beneath the rotatable member 15 and is tied to the respective string 13.

The fiat spring` or reed 21 is 4of the same frequency or nearly the same as that of the string to which it is attached. Further, the tone of the piano string, has besides its fundamental a number of upper partials which are heard at the same time as the fundamental and which makes the tone ofthe instrument rich and pleasing` in quality. To preserve these upper partials, the cord 22 is preferably attac-hed to the string at. approximately one-twentieth of its vibrating length from either end.

F-or the purpose of imparting a continuous rotation to the member 1,5, I provide an electric motor 23 operatively connected with the member 15 by any suitable transmission means 24. The rotatable member 15 turns in the direction of the arrow but .if desired, the same may rotate in an opposite direction without affecting the 4operation of the mechamsm.

In operation, when one of the key levers 18 is depresed, the rod 19 moves upward and in turn lifts the pivoted arm 2O upward about its pivot, thus causing the. reed or spring 21 to pull the cord 22 taut about one-fourth the circumference of the rotatable member 15. As the friction between the cord and the member 15 increases, the cord will be caused to vibrate and will continue to do so as long as this condition exists. This principle is similar to'that produced by a bow passing over the strings of a violin, but in this instance the member 15 may be termed a rotatable bow In Figure 3 of the drawings, I have shown a slightly modied'form of my invention in which a helical spring 21 is substituted for the reed or flat spring 2l shown in the preferred form. The operation and action is identical to that of the preferred form so that a description of the same is not believed necessary.

In Figures t and 5, I have shown a still further modification in which the same elements are used as in the preferred form but the same are arranged slightly different'. Should the string be of considerable length as for instance in the lower register of a piano, it will not start with its fundamental quick enough for practical purposes, because of its mass. To overcome this objection, I provide either one of two methods. In Figure a, a reed or fiat spring 21A is mounted below the rotatable member l5 forward of the string 13 and is of nearly the same frequency as the fundamental of the string. Instead of attaching the end of the cord directly to the string, the said end is attached to the reed or spring 21A at a particular pointand the said reed or spring 21A connected with the string at a particular point by means of a link 25. In Figure 5, the cord 2Q passes about the string 13 and has its ends respectively connected to the reeds or strings 2l and 21A. lVhen the reed 2l is raised the cord 22 will slide about the string as much as the tension of the reed or spring 21A will permit.

In Figure 6 of the drawings, I have shown my invention as applied to a. Xylophone. Instead of connecting one end of the cord 22 to a spring, the same is connected with the bar 26 of the instrument above which is suspended a resonator 27. In Figure 7, I have shown the identical principle hereinbefore mentioned as applied to a diaphragm mounted within a horn 29. Having shown my invention as applied to various sonorous bodies capable of vibration, it will be appreciated that the same may be used on other types of instruments if desired.

That is claimed .asnew is 1. In a device of the class described,the,y

combin ati/on lof a Jsonorous gmember, a. Vvibratmzyfaneinber, yof fr approximatelyathe" same frequency,y as saidsonorous member, means I for initially. imparting, a..l vibrating. 1 actionfv to said Avibiatory. member, f andI means sus-V taining r,the v vibrating laction afterf *tl-het;V ae#`- tuation of, .s aid iirstpnreans .and ,l fon. transe; :thea1vibrationfytp ,v ,saidsonorousa niittin member, said lastineans including a rotatable member and an element for transmitting energy from said rotatable member to said sonorous member after being governed by said vibratory member.

2. In a device of the-class described, the combination of a sonorous member, a vibratory member of approximately the same frequency as said sonorous member, means for initially impart-ing` a vibratory action to said vibratory member, a rotatable member, and co-acting means for sustaining the vibrating action of said vibratory member after the actuation of said means and for transmitting the vibrations to said sonorous member.

3. In a device of the class described, the combination of a. sonorous member, a vibratory member of approximately the same frequency as said sonorous member, means for initially imparting a vibrating action to said vibratory member, a rotatable membei'` and coi-acting means for sustaining the vibrating action of said vibratory member after the actuation of said means and for transmitting the vibrations to said sonorous member, said co-acting means inclu-ding a iiexible member engageable with a friction producing surface provided on the peripheral surface of said rotatable member.

it. In a musical instrument, a sonorous member, a rotatable member having a friction producing surface thereon, a reed` means for vibrating said reed, and aflexible member engageable with said rotatable member and adapted to transmit energy from said rotatable member to said sonorous member, the said energy being governed by said reed.

5. In a musical instrument, asonorous member, a roller having a resinous peripheral surface, means for rotating said roller, a reed of approximately the same frequency as said sonorous member, a iiexible member connected with said reed and engaging said sonorous member, and normally disposed out of co-acting relation with said roller but in close proximity thereto and means fer .imparting aibratiolis te said ,reed Jf causing ,saidl ,iiexible'fmember to {frictionally f engage. said ,roller ysubstantially as and, for

the purpose,,specifiedVA l.. 

